Laminated sheet building material



Oct. 18, 1932. c. J. BECKWITH 1,883,485

LAMINATED SHEET BUILDING MATERIAL Filed Feb. 27. 1928 a MWM Patented Oct. 1 8, 1932 UNITED ST T S ATENT OFFICE CHARLES J. IBECKWITH, bl NEWYOBI, N. Y

T1013, 0] YORK, 11'. Y A

coaroaarron or NEW YORK assreuoa r0 J'OHNS-MANVILLE conrona LAMINATED SHEET BUILDING MATERIAL Application fled February 27, 1928. Serial 1T0. #57375.

Objects of the present invention are to provide composite sheet material for build- 1ng houses, refrigerators, switchboards, etc., which is free from the defects of wall boards as heretofore constructed and which has the "following advantages: structural strength This new Sheet building material is en..-

acterized by surface strata of suflicient hardness, stiffness and thickness to alford structural strength, in contradistinction to a surface coating of aper, cardboard or veneer board, and in ad have the roperty of taking a polish, so that in the pre erred embodiment, the surface may be rendered substantially as smooth as polished stone. This is particularly important for switchboards, refrigerators, etc. where'a smooth surface is essential not only for appearance but also for cleanliness. In the case of switchboards, for example a slight deosit of dust or oil lar el re uces the insuation characteristic. 0 ar as I am at present aware, best results are obtainable when usin for the surface strata, asbestos bonded in a ard dense mass with Portland cement, the asbestos preferabl being partl or wholly in fibrous form. owever, in t e broader aspect, the invention is not confined to this specific composition, but coinprehendsvariatlons having similar characteristics.

This invention is further characterized by one or more intermediate strataof relative] light, soft and'porous insulatin materia such as celotex, which is compose of bagasse are bonded together with suitable cementitious material. This intermediate material is relatively inexpensive and therefore reduces the cost for a iven overall thickness or finished board. Miami, it has. high insaluting qualities and owing to i" porous character contributes in lar edegree to the sound-proof qualit of the nished product, which 18 particular y important when the ma ition is so constituted as to .as the o terial is used for building walls, floors and ceilings, telephone booths, etc. However, perhaps the chief advantage in using such materlal between the hard surface layers is greatly to reduce the frangibilit of the product; whereas a solid board 0 asbestos or'the like is likely to crack or shatter if subjected to a heavy stress or sharp blow, by dividin" the hard material into two strata withre lativel soft material therebetween, the product is less subject to breakage, chiefly due to the cushioning action of the soft intermediate layer.

For the purpose of illustration the preferred embodiment is shown in the accompan ing drawing, wherein H designates the har surface strata and S the soft intermediate stratum. The respective layers may be formed separately and then cemented together under pressure but they are preferably moiilded together before the surface strata have completel set. While the intermediate layer may a so be incorporated before it has set, it is usually more convenient first to finish the intermediate layer and subsequently to apply the surface strata while wet, after which the whole is pressed to force the surface material into the surface irregularities of the porous core. In this wa the layers may be ultimately interconnected and held together by the cementitious component of the surface strata; also additional binding material (either like or different). may be applied to the surfaces of the intermediate layer before the surface layers are applied.

' As stated above, this laminatedboard is unique in that its surfaces may be polished, for example as follows: A flat faced grinding wheel of very fine natural or artificial stone is movedover the surface while rotating slowly, the surface being he t wet with water or other liquid during tie inding operation. After a short timethe, ne partlcles, which are abraded from-the sheet, form with the water a thick fluid or emulsion, and eration 'is' continued this emulsion is conso 'dated with the. surface to form a dense and smooth surface, the surface finall muminga glossy'sheen if the operation 1s continued long enough. T

While the surface thus formed possesses some porosity (for example enough to permit impregnation with asghalt or other dielectrie or waterproofing uids) it is extremely dense and has little or dirt. Indeed it may be waxed and polished to a high degree.

From the foregoing it will be evident that this improved building material may be em- .bond the layers together. 2. A laminated plo ed as either structural or finished material it is thorou hly weather: roof so that it may beexp it is ornamental,'fireproof, and non-corr ible' and it requires no solid backing and need not be painted.

Iclaiin: I 1. A laminated building material consisting of a'backing layer of relatively light and orous insulating material and one or'm'ore acingblayers complrisin fibrous mineral material onded in a land cement, the res tive layers formed separately, an the facing layer or lafyers integrated by compressive intrusion o the mineral cement while still wet into the surface irregularities of the backing'layer to uilding material consisting of a backing layer of relatively light and rous insulating material and one or more ac' layers com risin fibrous mineral terial nded in a ard ense mass with Portland cement, the res ective layers being formed separately, an the facing layer or lafyers integrated by com ressive intrusion o the mineral cement wh' e still wet into the surface irregularities of bond the layers together, and an additional bonding material between the la ers.

3. A process of making a laminated build- I in material, comprising a backi la er of refitively' light, soft and porous nsulating material and a face layer of mineral fiber. bonded in. a hard dense mass with Portland cement, the process being characterized by separate formation of the ayers and pressin the several layers together while the minera cement layer is still wet.

4; A process. of making a laminated buildirlgg material, comprising a bac la er of atively li ht, soft and porous msu ating material an a face layer of mineral fiber bonded 'in a hard dense mass with Portland cement, the process being characterized by separate formation of the ayers and pressin the several layers together while the mine cement layer is still wet, with the inter-position between the separately formed layers of an additional binding material of the char actsero'fadPgrtland eernIent. Y

i y me at ew ork New York this get dag of February,

naaaaas tendency to collect dust 'exteriorly o a buildirfi;

ard ense mass with Portthe backing layer to 

